Richard h



IIIcIIARDgII-I1IIoPIIINs,.on HINSDIILII, NEW HAMPSHIRE.

Letters BatentfNo`.104,457, dated June 21, 1870.

IMPRovEMENT `IN wenn The chedule `referred to in these Letters Patent andmaking part of the-name.

. Be-it known that I, RICHARD HENIIY HOPKINS, of Hinsdale, in ltheconnty of Cheshire and State of I New Hampshire, have invented an Improved Auger or Bit, cf which tllefollowing is a specification, reference being had to the accompanyingdrawing, in

Figurel 'represents asideelevation ofmyimproved 1* anger; i I l i n Figure 2, an end view; and

j Figure 3, a transverse section ythrough the same.

` I My invention isdcsigned more especially for boring I y andreamingholesfin 4maple-trees to secure thc sap 3 for sugar; and. i

The improvement consists in combining in a bit, a

` i u central point or gimlet,cntting lipsprojecting ,longi- `cudinally beyond fthe front cutting-edge of the bit, I `andsp'iraidouble concave calming-edges, gradually en- I `largin g from thepoirt to the heel of the auger, so that,

when boring a hole to diierent depths on successive s I A days, the'last boring shall ream ont thc'dried surface l of thclxcle, and thus produce anew ow of sap.

1. In the drawng- A represents a shank or stock, which may be inserted in a suitable handle or bra'ce; from this shank proceed two spiral concave tapering blades or cutters B, which make a bit, of gradually diminishing diameeter, terminating in cutting-lips I), and having the usual boring-point c, and cutting-edges c.

`The bit, it will he seen, acts both as a box-er and" as a reamer.

I do not broadly claim a bit or auger'having double concave cutting edges. n A I claim the auger, constructed as described, with double concave ,tapering and spiral cutting-blades, thehoringpoint c, and the cutting-edges b c'.

In testimony whereof Ihave hereunto subscribed my name.

IiIcHARD H. IIOPKINs.

Witnesses HENRY 0. COOLIDQE, GEOI S. WILDER'. 

